Before - Liquid Tag Reference

The before block tag runs its content before the main page template is rendered. Use it in a Liquid controller to extract parameters, validate input, execute actions (like adding to cart), and prepare data for downstream rendering.

:::note This tag works only inside a Liquid controller template (at controllers/<controller>/<action>.liquid). It is a silent no-op outside a controller. :::

When before runs

In a Liquid controller, execution flows through three phases:

1. {% before %} block — runs first
2. Standard action — the main controller logic
3. Page rendering — the template output
4. {% after %} block — runs after rendering
5. {% final %} block — runs after response sent

Syntax

```liquid

{% before %} {% assign product_id = current_request.params.id %} {% action “cart.add”, product_identifier: product_id, quantity: 1 %} {% params product_id: product_id %} {% endbefore %} ```

Property	Value
Tag Name	before
Type	Block tag
Source	StoreConnect

What’s available in before

• current_request.params — query string and form POST parameters
• All globals — current_store, current_customer, current_cart, current_product, etc.
• All tags — {% params %}, {% action %}, {% variables %}, {% redirect %}, {% respond %}

Common tasks in before

1. Extract and validate parameters

```liquid

{% before %} {% assign product_id = current_request.params.product_id %}

{% if product_id == blank %} {% respond body: ‘{“error”: “product_id required”}’, status: 400, layout: false %} {% endif %}

{% params product_id: product_id %} {% endbefore %} ```

2. Execute a built-in action

```liquid

{% before %} {% assign quantity = current_request.params.qty | default: 1 %} {% action “cart.add”, product_identifier: current_product.id, quantity: quantity %} {% params quantity: quantity %} {% endbefore %} ```

3. Redirect on a condition

```liquid

{% before %} {% if current_customer == blank %} {% redirect to: current_store.account_login_path %} {% endif %} {% endbefore %} ```

4. Set variables for rendering

```liquid

{% before %} {% variables page_title: “Checkout”, show_progress: true %} {% endbefore %} ```

Key behaviors

• Runs before rendering — anything set in before is available in the page template
• Can redirect — a redirect in before skips the standard action and all subsequent rendering
• Can respond — a response in before skips rendering entirely
• Validation first — use before to validate all input before executing actions

Redirects from before

A redirect in before is the most common flow: validate input, then either proceed to the standard action or redirect to an error page.

```liquid

{% before %} {% assign order_id = current_request.params.id %}

{% if order_id == blank %} {% redirect to: current_store.orders_path, alert: “Order ID required” %} {% endif %}

{% params order_id: order_id %} {% endbefore %} ```

If validation passes and no redirect occurs, the standard controller action runs next.

Related phases

• {% after %} — runs after the standard action and page template render; use for responses or post-render cleanup
• {% final %} — runs after the response is sent; use for fire-and-forget work like analytics
• See Liquid controller lifecycle for the complete flow